The present invention relates to an improved object location means for robot vision and optical systems.
Applications for industrial robots are presently restricted to simple repetitive tasks on production and assembly lines where components are delivered to the robot station under tightly controlled conditions. The principle reason for their limitation to such roles is the lack of an efficient and economical general technique to provide them with vision. Considerable effort is now being made in all technologically advanced countries, to provide a suitable robot vision system. The commercial implications of a satisfactory system are very considerable and could initiate a new major industry.
Until recently the only successful attempts at industrial or robot vision systems have been restricted to very simple application systems to locate and orient components on some form of conveyor belt. This type of situation is comparatively easy to handle since the system is tightly constrained to a well regulated two dimensional object field. Nonetheless, the logic systems required by contemporary designs, even for this simple case, usually need at least a powerful minicomputer.
The present applicants have described, in their co-pending Australian Patent Application No. 62020/86, a system directed to the more general problem of locating and recognizing objects in full three-dimensional space, which problem had not previously been solved. All other systems known to the present inventor are highly experimental and invariably use main frame or very high powered computers; even with this power, the problem of location cannot be properly solved. Many techniques using outlines, edge detection, shading assessment, color, visual flow fields and the like, have been tried individually and in combination, to reconstruct the three dimensional aspects of an object field seen by a television camera. The inevitable complexity of these techniques defies a good real-time solution even where the most powerful computers now available are used for the analysis.
The central problem in the general three-dimension case is in the recovery of the "depth" information from the two-dimensional image collected by a conventional camera or image system. The prior art provides no general technique for unambiguous recovery of the information lost irretrievably in the 3D to 2D transformation.